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Efficient Synthesis of Polyfunctionalized Benzenes in Water via Persulfate-promoted Benzannulation of α,β-Unsaturated Compounds and Alkynes
Published on: December 16, 2019
Imines that react with phenols in water over a wide pH range
Maki Minakawa1, Hai-Ming Guo, Fujie Tanaka
1Department of Molecular Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA.
The Journal of Organic Chemistry
|October 11, 2008
Summary
New cyclic imine derivatives react with phenols, including tyrosine in peptides. These reactions occur efficiently in water across a broad pH range and temperature, yielding Mannich products without catalysts.
Area of Science:
- Organic Chemistry
- Biochemistry
Background:
- Phenols, including tyrosine residues in peptides, are important biological molecules.
- Developing efficient methods for modifying phenols is crucial in chemical synthesis and drug discovery.
Purpose of the Study:
- To develop novel cyclic imine derivatives capable of reacting with phenols.
- To investigate the reaction conditions and scope for these imine derivatives with phenolic compounds.
Main Methods:
- Synthesis of novel cyclic imine derivatives.
- Conducting Mannich reactions between imines and various phenols, including tyrosine-containing peptides.
- Optimizing reaction conditions, including pH, temperature, and solvent (water).
Main Results:
- The developed cyclic imine derivatives effectively react with phenols.
- Reactions proceed smoothly in water over a wide pH range (2-10) and temperatures (room temperature to 37°C).
- Mannich products are obtained in good yields without the requirement for additional catalysts.
Conclusions:
- Novel cyclic imine derivatives offer a versatile platform for phenol modification.
- The developed methodology provides a simple, efficient, and environmentally friendly approach for synthesizing Mannich products in aqueous media.
- This method has potential applications in peptide modification and the synthesis of complex organic molecules.
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